Vacuum-pump.



A. O. ROESSLER.

VACUUM PUMP.

APPLIOATION FILED JUNE 2, 1910. RENEWED AUG. 24, 1914.

Patented 0013.20, 1914.

2 SHEETS-SHEET 1.

INVENTOR WITNESSES A TTOR/VE Y 8 X UNITED STATES" PrgEN'r onFIo AMANDUS c, ROESSLER, or rrmEoLA, NEW Yong.

VACUUM-1 11MB.

Specification of Letters Patent.

Patented Oct. 20, 1914..

Application filed June 2, 1910, Serial No. 564,557. Renewed August 24', 1914. Serial No. 858,345.

To all whom it may concern Be it known that I, AMANDUS C. Rouss- LER, a subject of the King of Great Britain, and residing at Mineola, in the county of Nassau and State of New York, have invented certain new and useful Improvements inVacuum-Pumps, of which the following is a specification, such as will enable those skilled in the art to which it appertains to make and use the same.

This invention relates to vacuum pumps, and the object thereof is to provide an improved device of this class which is simple in construction and operation and which possesses ahigh degree of efiiciency; a further object being to provide what is known as a rotary vacuum pump, the construction of which is such that the inlet side of the pump is enlarged over the outlet side and simultaneously with the closing of the inlet or suction port or passage, the outlet or exhaust port or passage'is opened, whereby a rapid and continuous dischargeis secured and whereby the pump operates without compression; and with these and other objects in View the invention consists in a device of the class specified, constructed v as hereinafter described and claimed.

The invention is fully disclosed in the following specification, of which the accompanying drawing forms apart, in which the separate parts of my improvement are designated by suitable reference characters, in each of the views, and in which Figure 1 is a sectional side view of my improved vacuum pump, the section being taken on the line 1-1 of Fig. 2; Fig. 2 a sectional view at right angles to that shown in Fig. 1, the section being on the line 2--2 of Fig. 1; Fig. 3 a plan view but showing a modification; Fig. l a partial section on the line 4l4 of Fig. 3, and ;Fig. .5 a view similar to Fig. 4 but showing a modification.

In the practice of my invention I provide a casing a composed of parallel side platesa and a central circular or drum-shaped member a said casing being provided with a base 0L formed integrally therewith or the arts thereof, and the separate parts thereof being bolted together in the usual manner.

Within the casing a and-formed by the parallel side plates a and the drum-shaped member a is a chamber 5 which is only approximately circular in form, the circular walls thereof being formed by the inner walls of the drum-shaped member a and the said chamber 12 being partially formed on a circle represented by the full line b and the dotted line 5 and the center of I which is at m, and one diameter of which is represented by the line c-o. Thea circle formedby the lines 6 and b, for the purpose of this description Will be called the true circle of the chamber 6 and the. diameter 0-0, the true diameter of said circle. A part ofone wall of the chamber 5 extending from the point marked 1 to the point tween the line cl and the dotted line b ,'and this enlargement of one side of the chamber 5 or the Wall thereof is formed on two different centers, that part extending from 3 to 2 being formed on the radius of a circle, the center of which is at y, whilethat part which extends from 2 ton: is formed on a radius of a circle, the center of which is at z and it will therefore be seen that the chamon or framed on three different centers, m, y, and a with three different radii.

The side plates a of the casing a are proin the chamber 1) is a rotary member 6 which is cylindrical in form and also preferably hollow and the ends of the rotary member 0 fit in the recesses a and movable loosely and radially through said. rotary member is a piston blade f, the, op osite end edges of which are provided with longitudinal recesses f which are segmental in cross secpackings f ,The enlargement of one side of the chamber 72 in the manner shown and described makes one side portion thereof, the inlet side or portion, larger than the other, or the outlet side or portion, and the rotary member 0 is mounted at one side of the line cc which forms the; diameter of the true circle of said chamber 1), and eccentrically to the center of the true circle and between said center and the inlet and outlet ports or passages apd the axial line of said rotary member is adjatruly circular portion of said chamber 1) or the walls thereof largement of the inlet or suction side of the pump there is a freer flow of gas or fluid thereinto and a consequent freer flow of gas or fluid from the receptacle or chamber that is being exhausted and the pump works without compression.

The chamber 5 is provided with aninlet ber b or the circular wall thereof is struck vided with circular recesses of and mounted tion, and in which. are mounted longitudinal cent to a line joining the extremities of the and by reason of the en marked 00 is enlarged, the enlarged portion being represented by the full line (1 or beor suction port 9, and with an Outlet or exhaust port g and the rotary member 6 is so mounted that it always bears on the wall of the chamber 6 at y, and when said rotary member is in the position shown in full lines in Fig? 1 it divides the chamber 1) so that the inlet side thereof is much larger than I the outlet side, and the axial line of said rotary member is at a predetermined point between the center a: of the true circle and the point y g The outlet or exhaust port or passage extends around the wall of the chamber 7) on the side which is approachedby the piston in the operation of the device from the point 9 to the point 9 which is preferably a little in excess of the distance the inlet and outlet ports or passages are apart or approximately ninety degrees around the said cha'mber. The packings f are free to turn in the recesses f in the opposite end edges of the piston blade 7, and the outer surfaces of said packings are so formed in cross section that they-bear on the circular wall of the chamber 1) at all times.

I also provide means for fully lubricating my improved vacuum pump and said means consist of an oil cup 72. mounted in one of the bearings k of the trunnions e of the rotary member 6, and said oil cup communicates with a radial passage 71. formed in the bearing 72?, and which communicates with an annular groove 6 in the trunnion 6 said trunnions being provided with longitudinal grooves e which communicate with a groove f in one side edge of the blade f, and which communicates with transverse passages f which communicate with a passage f (which extends longitudinally through said blade and the packings f are provided in their outer surfaces with grooves f andports or passages f which form a communication between said grooves f and the passage 7, and by means of this construction there is a film of oil maintained at all times in the grooves f of the packings f, and the walls of the chamber 1) are thoroughly lubricated at all times.

The rotary member '6 may be driven by a belt wheel 7 connected with one of the journals e thereof or in any desired manner, and as will be clearly seen on an examination of Fig. 1 which indicates various positions of the piston blade f in the operation of the device, the outlet or exhaust portg is opened by one end of said piston blade, as the other end of said piston blade passes across the opening of the inlet or suction port 9 and by reason of this operation there is no compression of air within the chamber 6 during the operation of said machine and the exhaust from said chamber is continuous and regular at all times and the fact that the inlet or suction side of the chamber 1) is larger than the outlet or exhaustside also facilitates the operation of the apparatus, as will be readily understood, the inflow of air being free and in large volume at all times.

In Figs. 3 and 4 I have shown a modification in which the chamber 7) is divided by a central transverse partition I) through which the rotary member 6 passes into two similar chambers 6 and the rotary member or cylinder 6 is provided with a radially movable piston blade and each of said chambers is provide with an inlet port and an outlet port 9 and the outlet port g of one of said chambers is connected with the inlet port of the other by a pipe 6, and by means of this construction the power of the vacuum pump is increased as will be readily understood. With the above described exceptions it will be understood that the details of the construction of the modification shown in Figs. 3 and 4 will be the same as in the construction shown in Figs. 1 and 2.

In Fig. 5 I have shown a modification of the construction shown in Figs. 3 and 4, in which the rotary member or cylinder 6 is provided with piston blades f which are arranged at right angles to each other and with this construction the operation of the pump will be more regular and uniform than when said blades are both arranged in the same plane as shown in Fig. 4:.

portion and a non-concentric portion described from'a plurality of different centers with different radii, so that the casing is of greater capacity: on one side than on the other. It will also be noted that the axis of rotationof the piston blade is located at one side of a vertical line passing through the axis of the cylindrical portion of the casing and on the side of said line adjacent to the portion of lesser capacity. It will also be seen that the interior surface of the casin is such that it will engage the ends of a1 equal chords passing through the axis of rotation'of the blade. 4

Having fully described my invention, whatI claim as new, and desire to secure by Letters Patent, is

1. In a vacuum pump the combination of a hollow casing having a truly concentric portion, and an enlarged non-concentric portion, whereby the casing is made of greater capacity on one side than the other, the curvature of the concentric and nonconcentric portions being such that the will engage th""ends of all equal chor s drawn through a center of rotation, a sliding piston blade iournaled within the casing on said center of rotation, said casing having an inlet port on the side of the casing of greater capacity and an outlet port on the side of lesser capacity, said ports being so disposed with respect to each other that the blade will commence to open the outlet port substantially at the same time that the inlet port is closed to avoid the compressing of the fluid within said casing.

2. In a vacuum pump, the combination with a casing having'a truly circular portion and an enlarged non-concentric portion, whereby the casing is of greater capacity on one side than on the other, a sliding piston blade journaled insaid'casing and having its axis of rotation disposed on the side of a vertical line passing through the axis of the truly circular portion,'adj acent to the side of the casing having the lesser capacity, and above said axis, the curvature of the said portions of the casing being such that theywill engage the ends of all equal chords passing through said axis of rotation of the blade, said casing having an inlet port on the side of greater capacity and an outlet port on the side of lesser capacity, and said ports being so located with respect to, each other that the blade will commence to open the outlet port substantially synchronously with the closing of the inlet port by the other end of said blade, to avoid compressing the fluid in said casing. In a vacuum pump the combination with a hollow casing having a truly cylindrical portion and a non-concentric portion described from a plurality of different centers with different radii, whereby the casing is made of greater capacity on one side than on the other, a sliding piston blade journaled eccentrically in said casing and having its axis of rotation located at one side of a vertical line passing through the axis of the truly cylindrical portion of the easing and on the side of the casing of lesser capacity, and located above the said axis, the interior surface of the casing being on such radii that it will engage the ends of all equal chords passing through the axis of rotation of said blade, said casing having an inlet port on the side of greater capacity,

located substantially at the beginning of said enlarged portion of the casing, and an outlet port on the side of lesser capacity and so located that said blade will commence to edges of the blade and the end walls of the casing and means communicating with said groovesvfor supplying oil thereto.

5. In a vacuum pump the combination with a casing, of a sliding rotary piston blade journaled eccentrically therein, and provided on its opposite longitudinal edges with oil grooves, extending longitudinally of said edges, whereby said grooves will carry a body of oil and effect a self sealing junction between the edges of the blade and the end Walls of the casing, said blade being also provided with an .oil passage extending from one end to the other, and with, lateral passages extending from said longitudinal passage to said longitudinal grooves.

6. In a vacuum pump, the combination with a casing of a sliding rotary piston blade journaled eccentrically therein and provided at each end with oil grooves, and also prorided at its opposite longitudinal edges with oil grooves extending longitudinally thereof, said blade being also provided with an oil passage extending longitudinally therethrough, and communicating at its ends with said end grooves, and said blade having also lateral passages extending from said longitudinal passage to said longitudinal groove.

7. In a vacuum pump, the combination with a casing, of a sliding rotary piston blade therein, provided at its opposite ends with oil grooves, extending parallel to the axis of rotation of the blade, said blade being also provided with a longitudinal passage extending therethrough, and communicating at its opposite ends with said end grooves.

8. In a vacuum pump, the combination with a casing of a sliding rotary piston blade journaled eccentrically therein, and provided at its opposite ends with recesses, packings movably mounted in said recesses and engaging the inner curved surface of the casing, said-packings being provided on their outer faces with grooves extending longitudinally thereof, and on their inner faces with ports communicating with said grooves, said blade being provided with an oil passage extending longitudinal therethrough and communicating With the said ports in said packings.

In testimony that I claim the foregolng as my invention I have signed my name n presence of the subscribing wltnesses this 1st day of June, 1910.

AMANDUS c. ROESSLER.

Witnesses:

C. E. MULREANY, B. M. RYERSON; 

